/*
 * Copyright 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System;
using System.Collections.Generic;

using ZXing.Common;
using ZXing.Datamatrix.Encoder;
using ZXing.QrCode.Internal;

namespace ZXing.Datamatrix
{
   /// <summary>
   /// This object renders a Data Matrix code as a BitMatrix 2D array of greyscale values.
   /// </summary>
   /// <author>dswitkin@google.com (Daniel Switkin)</author>
   /// <author>Guillaume Le Biller Added to zxing lib.</author>
   public sealed class DataMatrixWriter : Writer
   {
      public BitMatrix encode(String contents, BarcodeFormat format, int width, int height)
      {
         return encode(contents, format, width, height, null);
      }

      public BitMatrix encode(String contents, BarcodeFormat format, int width, int height, IDictionary<EncodeHintType, object> hints)
      {
         if (String.IsNullOrEmpty(contents))
         {
            throw new ArgumentException("Found empty contents", contents);
         }

         if (format != BarcodeFormat.DATA_MATRIX)
         {
            throw new ArgumentException("Can only encode DATA_MATRIX, but got " + format);
         }

         if (width < 0 || height < 0)
         {
            throw new ArgumentException("Requested dimensions are too small: " + width + 'x' + height);
         }

         // Try to get force shape & min / max size
         var shape = SymbolShapeHint.FORCE_NONE;
         var defaultEncodation = Encodation.ASCII;
         var minSize = new Dimension(width, height);
         Dimension maxSize = null;
         if (hints != null)
         {
            var requestedShape = hints.ContainsKey(EncodeHintType.DATA_MATRIX_SHAPE) ? (SymbolShapeHint?)hints[EncodeHintType.DATA_MATRIX_SHAPE] : null;
            if (requestedShape != null)
            {
               shape = requestedShape.Value;
            }
            var requestedMinSize = hints.ContainsKey(EncodeHintType.MIN_SIZE) ? (Dimension)hints[EncodeHintType.MIN_SIZE] : null;
            if (requestedMinSize != null)
            {
               minSize = requestedMinSize;
            }
            var requestedMaxSize = hints.ContainsKey(EncodeHintType.MAX_SIZE) ? (Dimension)hints[EncodeHintType.MAX_SIZE] : null;
            if (requestedMaxSize != null)
            {
               maxSize = requestedMaxSize;
            }
            var requestedDefaultEncodation = hints.ContainsKey(EncodeHintType.DATA_MATRIX_DEFAULT_ENCODATION) ? (int?)hints[EncodeHintType.DATA_MATRIX_DEFAULT_ENCODATION] : (int?)null;
            if (requestedDefaultEncodation != null)
            {
               defaultEncodation = requestedDefaultEncodation.Value;
            }
         }


         //1. step: Data encodation
         String encoded = HighLevelEncoder.encodeHighLevel(contents, shape, minSize, maxSize, defaultEncodation);

         SymbolInfo symbolInfo = SymbolInfo.lookup(encoded.Length, shape, minSize, maxSize, true);

         //2. step: ECC generation
         String codewords = ErrorCorrection.encodeECC200(encoded, symbolInfo);

         //3. step: Module placement in Matrix
         var placement =
             new DefaultPlacement(codewords, symbolInfo.getSymbolDataWidth(), symbolInfo.getSymbolDataHeight());
         placement.place();

         //4. step: low-level encoding
         return encodeLowLevel(placement, symbolInfo);
      }

      /// <summary>
      /// Encode the given symbol info to a bit matrix.
      /// </summary>
      /// <param name="placement">The DataMatrix placement.</param>
      /// <param name="symbolInfo">The symbol info to encode.</param>
      /// <returns>The bit matrix generated.</returns>
      private static BitMatrix encodeLowLevel(DefaultPlacement placement, SymbolInfo symbolInfo)
      {
         int symbolWidth = symbolInfo.getSymbolDataWidth();
         int symbolHeight = symbolInfo.getSymbolDataHeight();

         var matrix = new ByteMatrix(symbolInfo.getSymbolWidth(), symbolInfo.getSymbolHeight());

         int matrixY = 0;

         for (int y = 0; y < symbolHeight; y++)
         {
            // Fill the top edge with alternate 0 / 1
            int matrixX;
            if ((y % symbolInfo.matrixHeight) == 0)
            {
               matrixX = 0;
               for (int x = 0; x < symbolInfo.getSymbolWidth(); x++)
               {
                  matrix.set(matrixX, matrixY, (x % 2) == 0);
                  matrixX++;
               }
               matrixY++;
            }
            matrixX = 0;
            for (int x = 0; x < symbolWidth; x++)
            {
               // Fill the right edge with full 1
               if ((x % symbolInfo.matrixWidth) == 0)
               {
                  matrix.set(matrixX, matrixY, true);
                  matrixX++;
               }
               matrix.set(matrixX, matrixY, placement.getBit(x, y));
               matrixX++;
               // Fill the right edge with alternate 0 / 1
               if ((x % symbolInfo.matrixWidth) == symbolInfo.matrixWidth - 1)
               {
                  matrix.set(matrixX, matrixY, (y % 2) == 0);
                  matrixX++;
               }
            }
            matrixY++;
            // Fill the bottom edge with full 1
            if ((y % symbolInfo.matrixHeight) == symbolInfo.matrixHeight - 1)
            {
               matrixX = 0;
               for (int x = 0; x < symbolInfo.getSymbolWidth(); x++)
               {
                  matrix.set(matrixX, matrixY, true);
                  matrixX++;
               }
               matrixY++;
            }
         }

         return convertByteMatrixToBitMatrix(matrix);
      }

      /// <summary>
      /// Convert the ByteMatrix to BitMatrix.
      /// </summary>
      /// <param name="matrix">The input matrix.</param>
      /// <returns>The output matrix.</returns>
      private static BitMatrix convertByteMatrixToBitMatrix(ByteMatrix matrix)
      {
         int matrixWidgth = matrix.Width;
         int matrixHeight = matrix.Height;

         var output = new BitMatrix(matrixWidgth, matrixHeight);
         output.clear();
         for (int i = 0; i < matrixWidgth; i++)
         {
            for (int j = 0; j < matrixHeight; j++)
            {
               // Zero is white in the bytematrix
               if (matrix[i, j] == 1)
               {
                  output[i, j] = true;
               }
            }
         }

         return output;
      }
   }
}